Proving/Disproving: U and V Intersection in Rn

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So for my homework I have to prove (or disprove) this statement:

If U, V are two subspaces of Rn then U \cap V \neq \phi.

I just want to make sure; \phi is the null set right? The set with nothing in it?
 
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jkm89 said:
So for my homework I have to prove (or disprove) this statement:

If U, V are two subspaces of Rn then U \cap V \neq \phi.

I just want to make sure; \phi is the null set right? The set with nothing in it?

Yes it's the empty set. However the symbol isn't the greek letter phi, but a symbol of its own based on the letter Ø (a letter in some alphabets).

Compare
\phi \quad \emptyset
The first is phi and the second is "empty set".

See http://en.wikipedia.org/wiki/Empty_set#Notation" for a bit more information.
 
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rasmhop said:
Compare
\phi \quad \emptyset
The first is phi and the second is "empty set".

This is why I got used to writing \varphi for phi. Although I never learned if there is a proper time to use \phi and a proper time to use \varphi.
 

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